34709
2013
2013
eng
882
886
5
10
12
article
Nature Publ. Group
London
1
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Speed limit of the insulator-metal transition in magnetite
As the oldest known magnetic material, magnetite (Fe3O4) has fascinated mankind for millennia. As the first oxide in which a relationship between electrical conductivity and fluctuating/localized electronic order was shown(1), magnetite represents a model system for understanding correlated oxides in general. Nevertheless, the exact mechanism of the insulator-metal, or Verwey, transition has long remained inaccessible(2-8). Recently, three- Fe- site lattice distortions called trimeronswere identified as the characteristic building blocks of the low-temperature insulating electronically ordered phase(9). Here we investigate the Verwey transition with pump- probe X- ray diffraction and optical reflectivity techniques, and show how trimerons become mobile across the insulator-metal transition. We find this to be a two- step process. After an initial 300 fs destruction of individual trimerons, phase separation occurs on a 1.5 +/- 0.2 ps timescale to yield residual insulating and metallic regions. This work establishes the speed limit for switching in future oxide electronics(10).
Nature materials
10.1038/NMAT3718
1476-1122
1476-4660
wos:2011-2013
WOS:000324736000012
Schussler-Langeheine, C (reprint author), Univ Cologne, Inst Phys 2, Zulpicher Str 77, D-50937 Cologne, Germany., christian.schuessler@helmholtz-berlin.de; hdurr@slac.stanford.edu
Stanford Institute for Materials and Energy Sciences (SIMES)
[DE-AC02-76SF00515]; LCLS by the US Department of Energy, Office of
Basic Energy Sciences; Stanford University through the Stanford
Institute for Materials Energy Sciences (SIMES); Lawrence Berkeley
National Laboratory (LBNL) [DE-AC02-05CH11231]; University of Hamburg
through the BMBF priority programme FSP [301]; Center for Free Electron
Laser Science (CFEL); FOM/NWO; Helmholtz Virtual Institute Dynamic
Pathways in Multidimensional Landscapes; DFG [SFB 608]; BMBF [05K10PK2];
SFB [925]; European Union Seventh Framework Programme [280555]; Italian
Ministry of University and Research [FIRB-RBAP045JF2, FIRB-RBAP06AWK3]
S. de Jong
R. Kukreja
C. Trabant
N. Pontius
C. F. Chang
T. Kachel
Martin Beye
Florian Sorgenfrei
C. H. Back
B. Braeuer
W. F. Schlotter
J. J. Turner
O. Krupin
M. Doehler
D. Zhu
M. A. Hossain
A. O. Scherz
D. Fausti
F. Novelli
M. Esposito
W. S. Lee
Y. D. Chuang
D. H. Lu
R. G. Moore
M. Yi
M. Trigo
P. Kirchmann
L. Pathey
M. S. Golden
Marcel Buchholz
P. Metcalf
F. Parmigiani
W. Wurth
Alexander Föhlisch
Christian Schuessler-Langeheine
H. A. Duerr
Institut für Physik und Astronomie
Referiert
36859
2011
2011
eng
3
18
98
article
American Institute of Physics
Melville
1
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Time-resolved resonant soft x-ray diffraction with free-electron lasers femtosecond dynamics across the Verwey transition in magnetite
Resonant soft x-ray diffraction (RSXD) with femtosecond (fs) time resolution is a powerful tool for disentangling the interplay between different degrees of freedom in strongly correlated electron materials. It allows addressing the coupling of particular degrees of freedom upon an external selective perturbation, e. g., by an optical or infrared laser pulse. Here, we report a time-resolved RSXD experiment from the prototypical correlated electron material magnetite using soft x-ray pulses from the free-electron laser FLASH in Hamburg. We observe ultrafast melting of the charge-orbital order leading to the formation of a transient phase, which has not been observed in equilibrium.
Applied physics letters
10.1063/1.3584855
0003-6951
wos:2011-2013
182504
WOS:000290392300037
Pontius, N (reprint author), Helmholtz Zentrum Berlin Mat & Energie GmbH, Inst Methods & Instrumentat Synchrotron Radiat Re, Albert Einstein Str 15, D-12489 Berlin, Germany., niko.pontius@helmholtz-berlin.de
German Bundesministerium fur Bildung und Forschung [FSP 301]; DFG [SFB
608, SFB 484]; European Union; U.S. Department of Energy, Office of
Basic Energy Sciences [DE-AC02-76SF00515]
N. Pontius
T. Kachel
C. Schüssler-Langeheine
W. F. Schlotter
Martin Beye
Florian Sorgenfrei
C. F. Chang
Alexander Föhlisch
W. Wurth
P. Metcalf
I. Leonov
A. Yaresko
N. Stojanovic
Martin Berglund
N. Guerassimova
S. Duesterer
H. Redlin
H. A. Duerr
Institut für Physik und Astronomie
Referiert